Our review of the original DIR-655 is one of our most-viewed wireless router reviews, befitting its status as one of the most successful draft 802.11n routers. Since its original release, D-Link has continued to enhance the product, adding 9K jumbo frame support awhile back for its gigabit Ethernet switch and more recently adding its SharePort USB-sharing feature (see this part of the DIR-825 review for the quick poop on SharePort).

The other thing that D-Link has done is rework the 655's innards, mainly with an eye for manufacturing cost reduction. The current revision is A4 and the natural question is whether D-Link has sacrificed performance along with reducing cost.

Figure 1 is a shot of the original 655 with its top cover removed. It used a mini-PCI radio and nice metal heatsinks on the Ubicom 5160U SoC and Vitesse VSC7385 Gigabit Ethernet switch. 16 MB of RAM and 4 MB of flash made up the rest of the design.

Figure 1: DIR-655 original inside view

The mini-PCI radio module was an Atheros AR5BMB71 reference design using an AR5416 Baseband / MAC and AR2133 3T3R 2.4 GHz radio.

Figure 2: Original mini-PCI radio module

Figure 3 shows the A4 version board. The radio has been integrated into the main board and uses a more recent Atheros chipset consisting of and Atheros AR9160 BB/MAC and AR9103 2.4 GHz 3x3 MIMO radio. I removed the ceramic heatsink pads and confirmed that the Ubicom IP5160U was still used as the router SoC. Lifting the pad on the larger device, however, showed that a Realtek RTL8366SR Gigabit switch was now used instead of the Vitesse device.

Figure 3: DIR-655 A4 board

I'm not going to review features, since little has changed. You can peruse the admin interface via the online emulator if you like or read the original review.

Routing Performance

Table 1 shows a slight improvement in routing performance, probably due more to the newer firmware than any hardware changes.

Test Description

A4 Throughput - (Mbps)

Original Throughput - (Mbps)

WAN - LAN

257

231

LAN - WAN

272

245

Total Simultaneous

269

254

Max. Connections

22,172

200

Firmware Version

1.21

1.04

Table 1: Routing throughput

Figure 4 shows what the throughput variation looks like for the WAN to LAN, LAN to WAN and simultaneous routing throughput tests.